Neuropharmacology of drug reward: Implications for drug addiction

Evidence from basic and clinical research in the last few decades indicates a major role of reward processes in drug addiction. Numerous studies implicate changes in the brain reward system in the initiation of drug use, the dependence phase of drug addiction, the withdrawal phase from drugs of abuse and the craving and relapse to drug-seeking behavior after a period of abstinence. Further, various neurotransmitter systems, including the dopamine, serotonin, glutamate and γ-aminobutyric acid systems, and their interconnections are involved in these changes and possible adaptations of the brain in response to drugs of abuse. This Research Topic will focus on recent and emerging evidence from basic research investigating how the reward system functions per se, to the most commonly used animal models of drug reward and to functional imaging studies in human subjects. These articles will address the neuropharmacology of drug reward from a neuronal, molecular and behavioral point of view. Importantly, the shared neuroanatomical and neurochemical pathways, and how such substrates are modulated by drugs of abuse will be thoroughly presented, in our efforts to understand the neuropharmacology of brain reward in response to drugs of abuse, summarise the current knowledge and potentially identify the next steps forward to the development of treatments for drug addiction.